Plc Programmable Logic Controller

spontaneous CONTROL OF HYDRAULIC government body USING PLC * Comp whatsoever Products & run * Abstract * Hydraulic System * Bow Compression appliance * round Diagram * Description * Chiller Unit * Solenoid valve * penetration To PLC * Softwargon * Advantages Of PLC * Introduction To PLC * Existing System * Proposed System * tend logic Diagram * die hard Logic Description * Energy Saving Calculation * For Existing rule * For Proposed Method * Advantages & Applications * Conclusion * References ABSTRACT angiotensin converting enzyme of the ch eithithernging constituent in factories, for the proper occasioning of the railroad car for the farseeing duration with capacity is to retain indispu board parameters within a unique(predicate) escape. Thus, in this paper, we fork out designed a run diagram for running PLC with the objective to windup(prenominal)ly withstand chink the hydraulic system. Our main requirement is to design a PLC which mint be commit ted to hydraulic system to implement the parameters and operations akin Temperature catching, compel detection, Lubrication, Automatic shape operation and Oil take detection.The mentioned parameters and operations slew be sensed and operated done PLC without any manual checking and operation. This saves much than power to industries by reducing the power consumption. INTRODUCTION In the end decades, the railroad cars employ in the industries were operated manually. So keeping its certain im portant parameters in a specific range was difficult. Also they keep non be checked out frequently. This results in improper functioning of the machine. Also, the machines gagenot work efficiently for a abundant term.For example, if the temperature of the fossil cover goes beyond the desired nourish it impart affect the machine function. Hence the machine accessories tummynot withstand this last temperature. This leads to the ab handling in machine and the durability of t he machine as well as gets reduced. Thus, the working machine requires frequent checking of certain parameters to maintain the treasure within the specified range for proper operation. The various parameters to be checked frequently atomic matter 18 1. Temperature detection 2. Lubrication 3. Automatic machine operation 4. Oil level detection . Pressure Thus we argon exploitation a PLC to have all these parameters. We atomic number 18 designing a melt diagram to subordination all the parameters involuntaryally. In this paper, we argon describing about the hydraulic drive system in which PLC is employ to restrainer its working. An introduction of PLC is provided and also the black market diagram overview. We go away be discussing about the advantages of PLC and also the power saving estimation in the industries by using PLC. The machine which we have taken crushstairs consideration for death penalty is BOW subject MACHINE.Also, the hair-raiser unit of measurement is described as it plays a major role for the power saving purpose. HYDRAULIC DRIVE SYSTEM Ahydraulic drive systemis a drive ortransmissionsystem that uses pressurizedhydraulic exemptto drivehydraulic machinery. The destination hydrostatic refers to the transfer of might from blend and insisting, not from thekinetic energyof the endure. Principle of a hydraulic drive Pascals lawis the basis of hydraulic drive systems. As the draw in the system is the same, the force that the precarious gives to the surroundings is t presentfore equal to pressure ? rea. In such a way, a mild plumbers helper feels a splendid force and a large speculator feels a large force. For an understanding of how a hydraulic system works, we must know the raw material principles, or laws, of hydraulics, that is, of confined crystal clears under pressure. This get out be made easier, however, if we first examine the manywhat simpler laws governing the behavior of liquids whenunconfined, that i s, in open containers. 1. Liquids in open containers. a. Density and specific gravity. The first characteristic of an unconfined liquid which interests us is its niggardliness.The density of a placid is theweight of a unit tidy sum of it. The unit of loudness habitually use in this text is the cubic foot the unit of weight normally apply is the pound. The standard of density, to which the densities of all other liquids are referred, is that of pure water at zero degrees centigrade (32 degrees Fahrenheit), and at sea-level atmospherical pressure. b. Force and pressure. A liquid has no shape of its own. It acquires the shape of its container up to the level to which it fills the container. However, we know that liquids have weight.This weight exerts a force upon all sides of the container, and this force stack be measured. on that pointfore, for unconfined liquids, that is, liquids in open containers, the pressure in pounds per satisfying andt on exerted by the liquid on th e posterior of the container is equal to the weight of the liquid on separately square inch of the merchant ship of the container. It must be emphasized that theweightof the liquid is here thought of as aforceexerted on the bottom of the container. express as a formula, we have Pressure = Force per unit areaIt is understood that the playscript pressure, when not otherwise qualified, meanspressure in pounds per square inch. This is called the nub force and is obtained by the formula Total Force = Pressure X Area The pressure exerted by a liquid on the bottom of a container is independent of the shape of the container, and depends only on the height and density of the liquid. 2. Liquids in en closed systems. a. Liquids are a undischarged deal incompressible. The following dickens basic principles pull up stakes help to explain the behavior of liquids when enclosed a) Liquids are practically incompressible. ) The applied pressure is transmitted equally in all directions at on ce. b. Increase of force with area. The ratio amid theforce applied to the small pistonand theforce applied to the bigger pistonis the same as the ratio betwixt thearea of the smaller pistonand thearea of the larger piston. Expressed as a proportion, therefore, we have Force on larger piston/Force on smaller piston = Area of larger piston/Area of smaller piston This means that the mechanical advantage obtainable by such an arrangement is equal to the ratio between the areas of the ii pistons.Since the area of the larger cylinder is 10 propagation as great as that of the smaller cylinder, pushing the smaller piston downward a distance of 1 inch will move the larger piston upward only 1/10 of an inch. The ratio between the switching of liquid in the smaller cylinder and the displacement of liquid in the larger cylinder is once again equal to the ratio between their areas. so that the amount of work (force X distance) done by the larger piston is exactly the same as the amount done by the smaller piston. c. Multiple units.It is not necessary to confine our system to a single line from the source of hydraulic power. Hydraulic power may be transmitted in many directions to do multiple jobs. stock clacker In practice we ordinarily need some whatsis which will deliver, over a period of time, a definite volume of fluid at the required pressure, and which will continue to deliver it as recollective as we desire it to do so. Such a device is called a gist. Basic principles of pumps. A hydraulic pump is a mechanical device which forcibly moves, or displaces, fluids.Various pumping principles are employed in the incompatible types of hydraulic pumps, but one fundamental principle applies to all a volume of fluid entering the intake outset, or port, is moved by mechanical action and forced out the discharge port. Hydraulic fluids. Almost any free-flowing liquid is suitable as a hydraulic fluid, as long as it will not chemically injure the hydraulic equipme nt. For example, an acid, although free-flowing, would patently be unsuitable because it would corrode the metallic parts of the system. a. Basic units of a hydraulic system. 1.A reservoir, or supply ar muchd combat vehicle, containing inunct which is supplied to the system as compulsory and into which the embrocate from the return line flows. 2. A pump, which supplies the necessary working pressure. 3. A hydraulic cylinder, or actuating cylinder, which uses the hydraulic energy developed in the pump to move the portal. 4. A cut-out valve, by means of which the pressure in the actuating cylinder may be maintained or released as desired. 5. A check valve, placed in the return line to tolerate fluid to move in only one direction. 6. Hydraulic lines, such as piping or hose, to connect the units to each other.The supply army ar more thand combat vehicle must have a capacity large enough to keep the entire system filled with oil and furnish additional oil to make good the inevit able losses from leakage. The cooler is vented to the reflexive teller machine thus atmospheric pressure (14. 7 pounds per square inch) forces the oil into the inlet, or suction, side of the pump. The tank is generally placed at a higher(prenominal) level than the other units in the system, so that gravity assists in nourishment oil into other units. The pump is the hand-operated, reciprocating piston type. SOLENOID VALVE Asolenoid valveis anelectromechanicallyoperatedvalve.The valve is controlled by an electrical currentthrough asolenoid in the incident of a 2-port valve the flow is switched on or off in the case of a three-port valve, the outflow is switched between the ii outlet ports. Multiple solenoid valves stub be placed unitedly on amanifold. Solenoid valves are the most frequently use control elements influidics. Their tasks are to shut off, release, dose, distribute or mix fluids. They are constitute in many finishing areas. Solenoids offer turbulent and safe and sound switching, high reliability, long service life, good medium compatibility of the materials used, low control power and compact design.There are many valve design variations. Ordinary valve can have many ports and fluid paths. A 2-way valve, for example, has 2 ports if the valve isclosed, thus the two ports are connected and fluid may flow between the ports if the valve isopen, then ports are isolated. If the valve is open when the solenoid is not energized, then the valve is termednormally open(N. O. ). Similarly, if the valve is closed when the solenoid is not energized, then the valve is termednormally closed. 1There are also 3-way and more than tangled designs.A 3-way valve has 3 ports it connects one port to either of the two other ports (typically a supply port and an exhaust port). Solenoid valve are also characterized by how they operate. A small solenoid can pay off a limited force. If that force is competent to open and close the valve, then adirect playings olenoid valve is possible. An judge relationship between the required solenoid forceFs, the fluid pressureP, and the hatchway areaAfor a direct acting solenoid value is Wheredis the orifice diam. A typical solenoid force might be 15N (3. lbf). An application might be a low pressure (e. g. , 10 pounds per square inch (69kPa)) gas with a small orifice diameter (e. g. ,3? 8in (9. 5mm) for an orifice area of 0. 11sqin (7. 1? 10? 5m2) and approximate force of 1. 1lbf (4. 9N)). When high pressures and large orifices are encountered, then high forces are required. To generate those forces, aninternally pilotedsolenoid valve design may be possible. 1In such a design, the line pressure is used to generate the high valve forces a small solenoid controls how the line pressure is used.Internally piloted valves are used in dishwashers and irrigation systems where the fluid is water, the pressure might be 80 pounds per square inch (550kPa) and the orifice diameter might be3? 4in (19mm). In som e solenoid valves the solenoid acts now on the main valve. Others use a small, know solenoid valve, cognize as a pilot, to actuate a larger valve. While the b connective of an eye type is actually a solenoid valve combined with a pneumatically pioneer valve, they are sold and packaged as a single unit referred to as a solenoid valve.Piloted valves require much less power to control, but they are noticeably slower. Piloted solenoids usually need full power at all times to open and stay open, where a direct acting solenoid may only need full power for a light period of time to open it, and only low power to pass it. A direct acting solenoid valve typically operates in 5 to 10 milli due southonds. The operation time of a piloted valve depends on its size typical great deal are 15 to 150 milliseconds. Solenoid valves are used influid powerpneumatic and hydraulic systems, to control cylinders, fluid power labors or larger industrial valves.Automaticirrigation sprinklersystems a lso use solenoid valves with an automaticcontroller. Domestic race machinesanddishwashersuse solenoid valves to control water entry into the machine. Solenoid valves are used indentist chairsto control air and water flow. In thepaintballindustry, solenoid valves are usually referred to simply as solenoids. They are commonly used to control a larger valve used to control the propellant (usually compressed air or CO2). In addition to this, these valves are now been used in nursing home water purifiers (RO systems).Besides controlling the flow of air and fluids, solenoids are used in pharmacology experiments, especially for patch-clamp, which can control the application of agonist or antagonist. Many variations are possible on the basic, one-way, one-solenoid valve described higher up * one- or two-solenoid valves * direct currentoralternating currentpowered * different number of ways and positions INTRODUCTION TO PLC AProgrammable Logic Controller, or PLC, is more or less a small computer with a constituent(a) operating system (OS). This OS is highly specialized to handle debut events in real time, i. . at the time of their occurrence. The PLC has introduce lines where sensors are connected to notify upon events (e. g. temperature above/below a certain level, liquid level reached, etc. ), and issue lines to signal any reaction to the incoming events (e. g. dough out an engine, open/close a valve, etc. ). The system is substance abuser platformmable. It uses a nomenclature called relay race Ladder or RLL (Relay Ladder Logic). The name of this language implies that the control logic of the earlier days, which was built from relays, is being simulated.The PLC is primarily used to control machinery. A program is written for the PLC which turns on and off products establish on input conditions and the internal program. In this aspect, a PLC is similar to a computer. However, a PLC is designed to be programmed once, and run repeatedly as needed. In fact, a crafty programmer could use a PLC to control not only simple devices such as a garage door opener, but their whole house, including switching lights on and off at certain times, monitoring a custom built security system, etc.Most commonly, a PLC is found inside of a machine in an industrial environment. A PLC can run an automatic machine for years with little human intervention. They are designed to withstand most harsh environments. When the first electronic machine controls were designed, they used relays to control the machine logic (i. e. press Start to start the machine and press Stop to stop the machine). A basic machine might need a wall covered in relays to control all of its functions. There are a few limitations to this type of control. * Relays fail. * The endure when the relay turns on/off. There is an entire wall of relays to design/ fit/troubleshoot. A PLC overcomes these limitations, it is a machine controlled operation. PLCs are becoming more and more intelligen t. In recent years PLCs have been integrated into electrical communicationsnetworks i. e. , all the PLCs in an industrial environment have been plugged into a network which is usually hierarchically organized. The PLCs are then supervised by a control center. There exist many proprietary types of networks. One type which is widely known isSCADA(Supervisory Control and Data Acquisition).The PLC is a purposeful machine control computer designed to read digital and parallel inputs from various sensors, execute a user defined logic program, and salve the resulting digital and analog end product set to various outfit elements desire hydraulic and pneumatic actuators, indication lamps, solenoid coils, etc. Scan wheel around study details vary between manufacturers, but most PLCs follow a scan-cycle format. Overhead Overhead includes testing I/O module integrity, substantiating the user program logic hasnt formd, that the computer itself-importance hasnt locked up (via a watchd og horologe), and any necessary communications.Communications may include traffic over the PLC programmer port, remote I/O racks, and other external devices such as HMIs (Human Machine Interfaces). remark scan A snaps juicy of the digital and analog set present at the input cards is saved to an input storehouse table. Logic doing The user program is scanned element by element, then ring by beat until the end of the program, and resulting values written to an output reposition table. Output scan Values from the resulting output remembrance table are written to the output modules. Once the output scan is complete the process repeats itself until the PLC is powered down.The time it takes to complete a scan cycle is, appropriately enough, the scan cycle time, and ranges from hundreds of milliseconds (on older PLCs, and/or PLCs with rattling complex programs) to only a few milliseconds on newer PLCs, and/or PLCs murder short, simple code. ADVANTAGES OF PLC * PLCs have flexibil ity (i. e. ) it is possible to use comely one model of PLC to run any one of the 15 machines. * In a PLC program circuit the PLC program can be used from any keyboard sequence in a matter of minute and revising is required. PLC has a large number of contacts for each coil in its programming. * increase technology makes it possible to compact move functions into smaller and less high-priced packages. * A PLC programmed circuit can be pre-un ad evaluated in the military officer or lab. The program can be typed in tested spy and modified if needed. * PLC circuit operation can be seen during operation directly on a CRT screen. * The operation drive on for the PLC program is very fast. * PLC is more reliable. * A PLC programmer who works in digital or Boolean control system can easily perform PLC programming. PLCs program cant be made unless the PLC properly unbarred and programmed. LADDER LOGIC DIAGRAM What is a Ladder Diagram? A Ladder Diagram is one of the simplest methods use d to program a PLC. It is a graphical programming language evolved from electrical relay circuits. Each program allegement is represented with a line, called the rung, that has all relevant inputs to the left(a) and the output to the right. The output device of a rung is energized if electric power can conceptually flow from the left side of the rung to the right side.Input devices are assumed to block the flow of power if they are not activated. During the execution of a runnel diagram, the PLC reads the verbalizes of all inputs, then determines the carrys of all outputs starting time from the rung at the top side, going down to the last rung, and finally updates the state of the output devices. * Naming Convention During the development of a PLC program, we must use specific names to come out the inputs, outputs, memory flags, timepieces and counters. PLC manufactures use a intermixture of nuzzlees in naming the inputs, outputs and other resources.A typical naming conven tion is to identify inputs with the letter I and outputs with the letter O, followed be a 1-digit number that identifies the slot number and a 2-digit number that identifies the position of the input or output in the slot. For example I100 refers to the first input of slot 1 O200 refers to the first output of slot 2. Some manufactures number the inputs or outputs starting from 00, while others use the number 01 to identify the first input or output. It is also common to use numbers like 400 e. t. c. The state of an output can be also used as an input in a ladder diagram.In such a case the PLC uses the state of the specific output device that is stored in the output image memory. * Relay Logic counsellings (XIC and XIO) Examine if Closed (XIC) &8212 &8212&8212 Use the XIC charge in your ladder program to determine if a human action is On. When the dictation is executed, if the objet dart addressed is on (1), then the discipline is evaluated as true. When the training is execut ed, if the bit addressed is off (0), then the counsel is evaluated as counterfeit. Examine if spread out (XIO) &8212&8212-/&8212&8212 Use the XIO instruction in your ladder program to determine if a bit is Off.When the instruction is executed, if the bit addressed is off (0), then the instruction is evaluated as true. When the instruction is executed, if the bit addressed is on (1), then the instruction is evaluated as false * Relay Logic readings Input modulation Sensing Positive transition Sense (PTS) The condition of the right link is ON for one ladder rung evaluation when a change from discharge to ON at the specified input is sensed. Negative Transition Sense (NTS) The condition of the right link is ON for one ladder rung evaluation when a change from ON to bump off at the specified input is sensed. * Output Instructions Output Energize (OTE) &8212-( )&8212 If the condition of the left link of the OTE is ON then the synonymous bit in the output data memory is set. The device wired to this output is also energized. Negative Output Energize (NOE) &8212&8212(/)&8212 If the condition of the left link of the OTE is OFF then the corresponding bit in the output data memory is set. The device wired output is also energized. Output bar/ eagerness (OTL) and Output Unlatch/Reset (OTU) If the condition of the left link of the OTL is momentary ON then the corresponding bit in the output data memory is set, and remains set even if the condition switches to the OFF state.The output will remain set until the condition of the left link of the OTU is momentary ON * Basic Logic break aways (OR, AND) Two Input OR Function The output is ON only if the two inputs are OFF. Two Input AND Function The output is ON if both of the two inputs are ON. * Basic Logic Functions (NAND,NOR) Two Input NAND Function The output is ON if any of the two inputs is OFF. Two Input NOR Function The output is ON if both of the two inputs are OFF. * Basic Logic Functions (EXOR, EXNOR) Two Input EXOR Function The output is ON if any of the two inputs is ON, but not both. Two Input EXNOR FunctionThe output is ON if both of the two inputs are either OFF or ON. * Set/Reset Latch Set/Reset Latch using a Hold-in contact Set/Reset Latch using Latch/Unlatch outputs Notes O100 means that the output is unchanged If both inputs are ON then normally the output is OFF, since the Unlatch rung appears last in the ladder diagram. * Timer Instructions Timer Instructions are output book of instructions used to time intervals for which their rung conditions are true (TON), or false (TOF). These are software timers. Their resolution and accuracy depends on a tick timer maintained by the microprocessor.Each timer instruction has two values (integers) associated with it accumulated Value (ACC) This is the current number of ticks (time-base intervals) that have been counted from the moment that the timer has been energized. P readapt Value (PR) This is a predetermined value set by the p rogrammer. When the hive away value is equal to, or greater than the planned value, a status bit is set. This bit can be used to control an output device. Each timer is associated with two status bits Timer modify Bit (EN) This bit is set when the rung condition to the left of the timer instruction are true.When this bit is set, the lay in value is incremented on each time-base interval, until it reaches the p fix value. do Bit (DN) This bit is set when the accumulated value is equal to the preset value. It is reset when the rung condition becomes false. * Timer On-Delay (TON) Instruction The TON instruction begins count when its input rung conditions are true. The accumulated value is reset when the input rung conditions become false. Timer ladder diagram example. natural timing diagram (Assume that Preset = 07). * Timer Off-Delay (TOF) InstructionThe TOF instruction begins count when its input rung makes a true-to-false transition, and continues counting for as long as the i nput rung remains false. The accumulated value is reset when the input rung conditions become false. Timer ladder diagram example. Typical timing diagram (Assume that Preset = 07). * Retentive Timer (RTO) Instruction The RTO instruction begins count when its input rung conditions are true. The accumulated value is retained when the input rung conditions become false, and continues counting after the input rung conditions become true. * Counter InstructionsCounter Instructions are output instructions used to count false-to-true rung transitions. These transitions are usually caused by events occurring at an input. These counters can be UP (incrementing) or DOWN (decrementing). Each counter instruction has two values (integers) associated with it Accumulated Value (ACC) This is the current number of the counter. The sign value is zero. Preset Value (PR) This is a predetermined value set by the programmer. When the accumulated value is equal to, or greater than the preset value, a st atus bit is set. This bit can be used to control an output device.Each counter is associated with two status bits Counter enable Bit (EN) This bit is set when a false-to-true rung condition to the left of the counter instruction is detected. Done Bit (DN) This bit is set when the accumulated value is equal to the preset value. It is reset when the rung condition becomes false. The maximal count value is 9999*. After a maximum count is reached, the counters reset and start counting from zero. * Count-up (CTU) Instruction The CTU instruction increments its accumulated value on each false-to-true transition at its input, starting from 0. Counter ladder diagram example.Typical timing diagram (Assume that Preset = 10). * Count-down (CTD) Instruction The CTD instruction decrements its accumulated value on each false-to-true transition at its input, starting from 0. Counter ladder diagram example. Typical timing diagram (Assume that Preset = -10). * The Reset (RES) Instruction The RES ins truction resets timing and counting instructions. When the RES instruction is enabled it resets the following. CountersAccumulated value, Counter Done Bit , Counter Enabled Bit. Timers Accumulated value, Timer Done Bit, Timer Timing Bit, Timer Enable Bit.Reset ladder diagram example. ADVANTAGES diligence * Automatic control of machine. * Free from manual operation and frequent checking. * Machine fault is reduced. * Energy consumption is reduced. * This method can save more power. * Industrial application in the first place used for boiler production. * Drilling and dull applications. * This applications can be utilise for all machines in BHEL. BOW CORRECTION MACHINE These are the specifications of the bow correction machine currently in use. MACHINE BOW CORRECTION MACHINE CAPACITY 600 TONS piston chamber BORE 550 MM RAM DIAMETER 520 MMDAYLIGHT 3000 MM THROAT 1700 MM STROKE 500 MM CONNECTED stretch 60+1+5 HP TOTAL WEIGHT 80 TONS BOLSTER SIZE 1500*2000*200 MM SPEEDS OF OPERATI ON 15mm/sec APPROACH6mm/sec PRESSING60mm/sec RETURN PURPOSE. In the pipes used in boilers, small pipes are attached using welding. This welding makes the pipe to bent. Thus its protrude becomes uneven and makes it imperfect to be used in boilers. In this case this machine is used. Using this machine the bents and bows can be straightened and makes the pipes perfect to be used in the boilers. CIRCUIT DIAGRAM OPERATION.The hydraulic circuit is designed to achieve fast progress zip, slow pressing speed and fast return speeds by use of a single pump. The fast approach speed is achieved by ensuring that the cylinder ram moves down through its self weight or what is termed as gravity string up. To achieve gravity fall of the cylinder of the cylinder it is important to ensure that at all times the pressure in return line is minimum 5 kg/ cm2. On starting the motor the pump delivery is directed to the tank through unloading type stand-in valve no. 4. The same flow is directed to t he Z1 lines of catridge valves 5 7, which ensures that the valves are closed.On operation of solenoid S1 of main reliever valve the pump flow is directed to the catridge valves, however due to differential areas the catridges are comfort closed and pump reaches system pressure and unloads to tank through relief valve 4. On operation of solenoid S2( valve 6) along with S1, Port A of solenoid valve no. 6 is connected to tank Y1 which facilitates opening of catridge valve 5 and therefrom the oil flows into the frontward line of the cylinder resulting in downward movement. At the same time the oil in the return line of the cylinder is connected to tank at the set pressure through valve no. 11.Hence the cylinder moves down with slow pressing speed. On operation of solenoid S4 ( valve 8) along with S1 S2 the X port of catridge valve 10 is connected to tank through valve 8, 6 and port Y1 that ensures the opening of the catridge valve 10. Opening of the catridge valve ensures that the return line is connected directly to tank and therefore the cylinder oves down with its self weight and fast approach speed is achieved. At the same time prefill valve 14 opens to fill the cylinder previous area with oil. To set the maximum fast approach speed valve 10 is provided with a stroke adjustment setting.On operation of solenoid S3(valve 6) along with S1, port B of solenoid valve no. 6 is connected to tank Y1 which facilitates opening of catridge valve 7 and hence oil flows into the return line of the cylinder. At the same time since A port of solenoid valve no. 6 is connected to pump port X4 is also connected to pump, ensures the opening of prefill valve no 14 and that the forward line of the cylinder is connected back to tank. This results in reverse movement of the cylinder. Pressure relief valve 9 is provided to ensure smooth deceleration of the cylinder from fast approach to pressing.The valve ensures that the pressure in X port of the cartridge valve does not over come set pressure therby ensuring that the valve closes slowly reducing jerks. The hot oil from the machine is then sent to the chiller unit to reduce its temperature. chiller unit of measurement In the chiller unit, the refrigerating is used to cool down the hot oil from the machine. REFRIGERATION A liquid whose Saturation temperature at normal atmospheric pressure is below the temperature that is to be produced by infrigidation is chosen as the working liquid in the refrigerant.Such a liquid will evaporate at lower temperatures and will absorb hear as it does so. This inflame is extracted from the surroundings. The evaporation formed in this way is compressed in a compressor. After compression the refrigerant may be in the vapour state or, in the liquid state if its temperature after compression is not greater than the saturation temperature at that increase pressure. The low temperature vapour is purifyd in a condenser, in doing so it lowers its temperature below the surr oundings . direct the condensed liquid is rarifyed to a lower pressure and the cycle of refrigeration is repeated.REFRIGERATION CYCLE * Compressors are used in vapour compression cycles. It is the center of the system and it sucks low-pressure refrigerant vapour from the evaporator and compresses it to a pressure corresponding to the saturation temperature that will be higher than continuously re-circulate the refrigerant through the system. * Air-cooled condensers are heat exchangers,which reject heat from the condensing refrigerant to the atmosphere. * The function of condenser in a refrigerated system is to de-superheat and condense the compressed discharge refrigerant vapour.High-speed fans are mostly used to speed up the process. * At the exit of the condenser the refrigerant loses temperature but still is in high-pressure state. The temperature falls down a little high to the ambient. * Dryers are mainly used to capture the wet content if any mixed with the refrigerant. Whe n the refrigerant passes through its thin filter mesh the moisture gets trapped on the silica gel and clean refrigerant flows through. * circumscribe valve(also called as Expansion valve)is also a very important cistron of the vapour compression refrigeration system.The function of an expansion device is to expand the liquid refrigerant from the condensing pressure to the evaporating pressure. Also it throttles the required flow into the evaporator depending on the load conditions. Commonly used expansion devices are capillary vessel tubes, thermostatic expansion valves and constant pressure expansion valves. * Any liquid when evaporate creates a cooling effect. Same applies here, when the refrigerant exists expansion valve it is partially in vapour state at low temperature and pressure. It flows through the evaporator and exchanges heat with the surroundings. After existing the evaporator it has gained heat from the surrounding media, thus lowering the temperature in the freezing compartment. This superhead vapour passes further and is drawn by the compressor, which compresses it,and delivers to condenser, thus, completing the refrigeration cycle. The ladder diagram used in this machine is CNT_ON CNT_OFF MEM_1 MEM_1 MEM_1 MOT_ON MOT_ON MOT_OFF VAL4_ONVAL4_ON VAL4_ON MEM_2 MEM_2 S1 S2 S3 S4 S5 FAST_APP FAST_APP S1 S2 S3 S4 S5 PRESS_ON TIMER T1 preset 15 ACC 0 PRESS_ON S1 S2 S3 S4 S5 HOLD_ON HOLD_ON HOLD_MEM HOLD_MEM S1 S2 S3 S4 S5 RET_ONRET_ON VAL4_ON COMPARE TEMP_ON45 TEMP_ON MEM_4 MEM_4 CHILLER_ON TEMP_ON CHILLER_OFF COMPARE TEMP_ON45 LOW_SEN ALARM_ON V_LOW_SEN TANK_ONPRES_ON VAL14_ON animate SYSTEM * There is no temperature detection system. Hence, the chiller unit has to function continuously irrespective of hydraulic oils temperature. * Possibilities of machine can run due to friction since there is no Indication of oil in tank. * The chiller unit is running continuously hence there is a possibilities of lot of Energy consumption losses. * Th ere is no automatic control for the whole machine. * There is no automatic function for declamping and lubrication. There is no oil level sensor in the hydraulic tank to sense the oil level in the tank. * Relays are used which is not automatic and inefficient. HORIZONTAL BORING MACHINE HYDRAULIC TANK CHILLER unit PUMP SOLENOID VALVE PROPOSED SYSTEM * In this method there is a temperature sensor which is used to sense the temperature of the oil in the hydraulic tank. * The chiller unit will be turned on only when the oil temperature gets increased with the specified value of oil temperature * Friction of the machine can be reduced by implementing the lubrication function. Oil level in the hydraulic tank can be detected by using an oil level sensor . * Two types of oil level sensor is used. I. downhearted level sensor II. Very low level sensor So that we can avoid the machine running in dangerous condition. * both the operation in one axis (x or y or z) can be operated by a single push clit switch. * Declamping and lubrication function takes place automatically. ENERGY SAVING CALCULATION * WITH CHILLER UNIT WORKING CONTINUOUSLY For continuous running of chiller unit the motor consumes 18KW. Per day sunrise -4hrs night -8hrs so chiller unit runs wholly 12hrs a day. 8KW*12hrs=216 KWhr The chiller unit consumes 216KWhr per day. For electricity 1unit= Rs. 5 Therefore 216*5= 1080 So for 216 unit it costs Rs. 1080 per day. 1080*30=Rs. 32,400 For 1month it costs Rs. 32,400 32400*303= Rs. 98,17,200 For 1year it costs Rs. 98,17,200. * WITH PLC For automatic on/off of chiller unit the motor consumes 10KW. Per day morning -4hrs night -8hrs so chiller unit runs totally 12hrs a day. 10KW*12hrs=120KWhr The chiller unit consumes 120KWhr per day. For electricity 1unit= Rs. 5 Therefore 120*5= 600 So for 120unit it costs Rs. 600 per day. 600*30=Rs. 8,000 For 1month it costs Rs. 18,000 18000*303= Rs. 54,54,000 For 1year it costs Rs. 54,54,000. CONCLUSION This project mainly focuses the oil temperature and oil level detection and also the automatic control of machine. Implementation of this project is simple and very economical. This applications can be implemented for all machines in BHEL. All the functions can be achieved through a single PLC program. The advantage of our project is used to eliminate manual checking and operation. The above mentioned parameters and operation can be sensed and operated through PLC.This project saves more power to industries by reducing the power consumption. REFERENCES 1. Allen bradely Instruction Set user manual by Rockwell Automation. 2. Programmable Logic Controllers Programming Methods and Applications by John R. Hackworth and Frederick D. Hackworth, Jr 3. Ladder logic fundamentals industrial control system fall 2006. 4. vigor FUNDAMENTALS HANDBOOK INSTRUMENTATION AND CONTROL Volume 2 of 2- U. S. Department of Energy Washington, D. C. 20585. 5. Automating Manufacturing Systems with PLCs (Version 5. 0, May 4, 200 7) -Hugh Jack